Re: ebuilds in XML

"Kevin Horn" <[email protected]> writes:

> very spiffy!  Obviously just a prototype, but it demonstrates your
> idea very nicely.  Using a system like this, one could store the
> metadata portion of an ebuild as XML, have the actual install script
> auto-generated, and thereby avoid having to rewrite a lot of common
> tasks in bash (or whatever shell language).  The XSLT could rapidly
> become non-trivial, but I think this is a great direction to
> explore.
> 
> Hmmm...could a particular package have one XML file, and a number of
> different XSLT templates for different platforms?  i.e. one XML file
> per package, and one XSLT file per platform, all packages use the
> same XSLT transform for a particular platform?
> 
> Hmmm, also, perhaps one might need several "layers" of XSLT
> transform...  XML + XSLT1 -> XML2 XML2 + XSLT -> Bash? install
> script I'm not even sure why you would do this, but it could come in
> handy?  maybe?

Not so much devil's advocate, but I will say that this sounds somewhat
nightmarish to write to me.

XML may be good for a lot of things, but it isn't a panacea -- it's
designed to mark up content, not to present a list of actions (which
is exactly what bash was desined for).  Using bash functions
alleviates the need to re-write common tasks.

> Ooooh!  This approach would also be useful for autogenerating
> certain docs or parts of docs.  e.g. Package description on website
> auto-generates details on deps, available USE flags, etc.
> 
> The more I think about this, the more I like it.  Anyone wanna play
> devil's advocate?

I tend towards the thought that while XML is very good for portability
of data, I don't ever want to have to write any by hand again.
Personally, I would want to implement common operations in $LANGUAGE,
devise some standard style of puttings things together in a file
(probably using ReStructured Text for documentation) then let the
automated tools take over.  Something like PyDoc would be be good for
reading about packages &c., we can also build utils to grab the
documentation out of the package, to make sure that packages have
everything in the right place when checked-in.

I think I quite like Gentoo's current ebuld syntax, actually.  It's
nice and easy to understand what's going on, at least on the surface.
Of course, underneath it could all be very different (and a Zynot
implementation of portage probably would be very different) but on the
surface it could still look very nearly the same.

OK,
-- 
Andrew Aylett | www.aylett.co.uk | 9.72 x 10^-21 parsecs per picosecond
[email protected] | answer==42 |  -- it's not just a good idea, it's the law!